Flexible Cable Assembly Conductive Barrier for Medical Implants
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Medical implants with electrical components face challenges in preventing ingress of body fluids due to electric fields, particularly in devices with fixed-polarity contacts and in flexible or volume-constrained applications, where conventional solutions like alternating voltages or rigid hermetically-sealed packages are not feasible.
Innovation Solution
A flexible electrical cable assembly with a conductive barrier layer that spatially averages the electric field to zero, using a coaxial layout with a conductive enclosure and insulating overmold layer to reduce field penetration and provide mechanical protection, allowing for flexible and compact implantation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rigid hermetically-sealed packages are used to protect electronics, then protection against body fluid ingress is improved, but flexibility and space constraints are worsened
Solution Approach 1:
The patent uses a flexible cable assembly with a hermetic seal that can be bent and folded, replacing rigid hermetically-sealed packages. The flexible cable includes a hermetic seal that maintains protection against body fluid ingress while allowing the device to conform to curved surfaces and fit in volume-constrained environments.
2Volume of stationary object
If barrier coatings are applied over electronics, then space is reduced, but protection against electric field induced ingress is worsened
Solution Approach 1:
The patent employs a conductive barrier layer that is held at a constant potential (ground or reference potential) to create an equipotential shield. This conductive layer, positioned between the electric field source and the barrier coating, eliminates the time-dependent electric field that would otherwise cause electromigration through the thin barrier coating, thereby maintaining both space efficiency and protection reliability.
3Reliability
If alternating voltage is used to reduce electric field induced ingress, then protection is improved, but compatibility with fixed-polarity devices is worsened
Solution Approach 1:
The patent introduces a conductive barrier layer as an intermediary element between the fixed-polarity electric field source and the surrounding body fluids. This conductive layer, when held at a constant potential, acts as a shield that blocks the electric field from causing electromigration, providing protection equivalent to alternating voltage without requiring voltage alternation, thus maintaining compatibility with fixed-polarity devices like batteries.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces electric field exposure to body fluids, enhancing device reliability and enabling flexible, compact implantation of medical devices by minimizing tissue exposure and preventing time-dependent ingress.
Implementation Method 1
A flexible electrical cable assembly with a conductive barrier layer that spatially averages the electric field to zero
Data Source
AI summary
An electrical cable assembly amenable to implantation into a body includes a flexible cable. The flexible cable includes a dielectric substrate, a conductor lead for conducting an electrical signal, a conductive barrier layer, and an overmold layer. The conductor lead is embedded within and surrounded by the dielectric substrate. The conductive barrier layer surrounds the dielectric substrate and encases the dielectric substrate and conductor lead in a cavity. The conductive barrier layer is a continuous material layer that is neither braided nor spiral wrapped and provides a hermetic barrier formed of a metallic or inorganic material. The overmold layer provides one or more of mechanical protection or strain relief to the conductive barrier layer.